Custom fields for multiple pages

What is the easiest way to use custom fields to load different sliders on different pages. What is the function I need to put in my functions.php file to make custom fields work. I’ve got a custom field set up on my home page as slidedeck_id but the functions I’ve tried haven’t worked (no I don’t want to show these functions here thanks). I just need to know how most people go about using custom fields.